Method and apparatus for applying radium-luminescent material



May 16, 1944.

M. R. SAXBY METHOD AND APPARATUS FOR APPLYING RADIUM-LUMINESCENT MATERIAL 12 Sheets-Sheet 1 Filed June 12, 1941 MARVIN R SAXBY I INVENTOR A OR @x V k M. R. SAXBY 2,348,929

-LUMINESCENT MATERIAL May 16, '1944.

METHOD AND APPARATUS FOR APPLYING RADIUM Filed June 12, 1941 12 Sheets-Sheet 2 MARV R S 2 Y BY A ORN M. R. SAXBY 2,348,929

METHOD AND APPARATUS FOR APPLYING RADIUM-LUMINESCENT MATERIAL May 16, 1944.

Filed June 12, 1941 12 Sheets-Sheet 3 y 16, 44. M. R. SAXYBY 2,348,929

METHOD AND APPARATUS FOR APPLYING RADIUM-LUMINESCENT MATERIAL Filed June 12, 1941 12 Sheets-Sheet 5 111., lu milmmmi llS Th lEl.

MARVIN R. SAXBY INVENTOR May 16, 1944. s x 2,348,929

METHOD AND APPARATUS FOR APPLYING RADIUM-LUMINESCENT MATERIAL Filed June 12, 1941 l2 Sheets-Sheet 6 llllll INVENTOR MARVIN R. SAX Y I A on Y May 16, 1944.

M. R. SAXBY 2,348,929

METHOD AND APPARATUS FOR APPLYING RADIUM-LUMINESCENT MATERIAL 12 Sheets-Sheet 7 Filed June 12 1941 /Z.? mllllh I /w I! /A MARVIN R. SAXBY INVENTOR May 16, 1944. sAXBY 2,348,929

METHOD AND APPARATUS FOR APPLYING RADIUM-LUMINESCENT MATERIAL Filed June 12, 1941 12 Sheets-Sheet 8 T5115. 1& M

MARVIN R. SAXBY INVENTOR May 16, 1944. s x 2,348,929

METHOD AND APPARATUS FOR APPLYING RADIUM-LUMINESGENT MATERIAL 2/4 254 #4 2% A, v 255 if? 1% .@:Z. l M t A 259 246 I w 267 6 g 4/?/ w 2 3 25 a 7 2.53

MARVIN R. SAXBY INVENTOR ATTORNE WWW y 16, 1944- M. rmsAxBY 2,348,929

' METHOD AND APPARATUS FOR'APPLYING RADIUM-LUMINESCENT MATERIAL Filed June 12, 1941 l2 Sheets-Sheet 1O Q I E/2,;'M ;7/////A ATTORNEY May 16, 1944. M. R. SAXBY 2,343,929

METHOD AND APPARATUS FOR APPLYING RADIUM-LUMINESCENT MATERIAL Filed June 12, 1941 12 Sheets-Sheet ll 245 JJ? 5 E E- 54a {I I m I 5 1 g 34d J47 a M J45 T; .ze. 555 355 MARVIN R. SAXBY INVENTOR y 16, 1944- M. R. SAXBY 2,348,929

METHOD AND APPARATUS FOR APPLYING RADIUM-LUMINESCENT MATERIAL Filed June 12, 1941 12 Sheets-Sheet l2 I MM IINMIHIIHHIIHHIIMMUNE.

MARVIN R. SAX BY INVENTOR Patented May 16, 1944 METHOD AND APPARATUS FOR APPLYING RADIUM-LUMINESCENT MATERIAL Marvin R. Saxby, Pleasant Plains, Staten Island,

N. Y., assignor of sixty per cent to George Murran, New York County, N. Y.

Application June 12, 1941, Serial No. 397,684

27 Claims. (Cl. 101-318) This invention relates to the application of radium-luminous material to a receiving surface, and with particularity to such application with a minimum of personal contact with the luminous material.

I am aware that machines have heretofore been proposed for applyin radium-luminous paint to such devices as clock and watch dials, with the object of avoiding personal contact with the paint material. However, for various reasons which will be pointed out herein, these prior proposals have not been entirely satisfactory. One of the main difiiculties encountered in machines of the type under consideration, is the necessity of maintaining the radium-luminous material uniformly distributed in its vehicle or liquid suspension. Because of the very heavy nature of the radium-luminous crystals or particle s, they tend to separate out very rapidly. Various means have heretofore been proposed to maintain the crystals uniformly distributed. Thus in one type of machine, the paint is carried in a tubular reservoir which is turned upside down at regular intervals to effect a mixing action on the paint However, because of the heavy character of the particles, they tend to compact and lodge at the ends of the reservoir. Furthermore, with the prior type of mixing device, it is neecssary to charge the reservoir with a considerable quantity of the paint so as not to interrupt the operation of the machine. I have found that this large quantity of charge causes the particles at the lower end of the reservoir to be subjected to considerable pressure by reason of the weight of the supervening column. This weight further tends to compact the crystals. In. addition where the charge is applied to the moving reservoir in large quantities, it is very difiicult to maintain its consistency or viscosity uniform over an extended period of time. Accordin ly, it is a principal object of this invention to provide an improved method and apparatus of supplying radiumluminescent paint to the printing ortransfer mechanism of an automatic applicator machine whereby the particles are at all times substantially uniformly distributed in the liquid vehicle, and the danger of compactin of the particles is reduced to a minimum.

I have found that with prior machines, the luminous efiiciency of the printed characters or indica varies considerably from batch to batch. and after careful investigation I have found that this variation results in great part from the pressure to which the crystals have heretofore been subjected during agitation and transfer to the printing surface. Furthermore, in prior machines the luminous paint must be ejected or expressed from the mixing reservoir into a mold to .form the indicia. Thus in one type of machine, a piston-like plunger is arranged for reciprocation within the reservoir and is operated by a rack and pinion to force the paint out through a nozzle attached to the reservoir. Inasmuch as the luminous efficiency is a function of the pressure to which the crystals are subjected, it is at once apparent that this prior method of forcing or expressing the paint results in a considerable loss in ultimate efiiciency as well as a waste of paint which is comparatively expensive.

Accordingly, it is another principal object of this invention to provide a method and apparatus for transferring radium-luminous material from a supply to a receiving surface while subjecting the crystal to a minimum of pressure and with a minimum waste.

In such devices as dials for clocks, watches, aeroplane instruments and the like, it is customary to provide the indicia on the dial in the form of raised characters employing an intermediate molding step. I-Ieretofore, in machines of ,the type designed to imprint such characters, the material after agitation in the reservoir, is transferred in a liquid or viscous state to a mold wherein are formed the respective solid indicia, and then after hardening the molded indicia are transferred from the mold to the final receiving surface. Therefore, it is another principal object of the invention to provide an improved process and apparatus for directly forming and printing raised characters or indicia of radium-luminous paint.

Another object is to provide a completely auto- Another feature relates to a novel mechanism for loading and stripping a plurality of rotating printing quills. Preferably and in accordance with the invention, the loading and stripping mechanism is adjustable to control the quantity of printing liquid or paint carried by the quills.

A further feature relates to a novel raisedcharacter printing device comprising a plurality of constantly rotating quills which are movable as a unit in a direction parallel to their axes of rotation, in conjunction with a special stripping shield for sharply delineating the boundary of the printed characters.

A feature of the invention relates to an automatic machine for printing raised characters comprising a bank of rotating printing quills which are movable bodily in a vertical direction, in conjunction with a horizontally movable trough for carrying a limited quantity of the printing medium into loading relation with respect to the quills.

A further feature relates to an automatic machine for printing raised characters comprising a trough-like member for receiving the printing medium, in conjunction with a vane-like distributor coacting with the trough to localize the supply of printing medium with a minimum of pressure thereon.

A further feature relates to an automatic machine for printing raised characters employing a paint-like printing medium, wherein the printing is effected by banks Of rotating quills past which the printing surface is moved, and a, reservoir containing the paint is moved between the quills and printed surface to load the quills, in conjunction with means for automatically controlling the amount of paint transferred to the quills from the reservoir.

Another feature relates to a novel form of inking carriage and supply reservoir for an automatic printing machine.

A further feature relates to an improved agitating and wiping arrangement for the ink-supply of an automatic printing machine employing radium-luminescent printing paint and the like.

A still further feature relates to the novel organization, arrangement and relative location of parts which constitute an improved and eflicient machine for printing with radium-luminescent paints and the like.

Fig. 1 is a front elevational view of a machine for carrying out the invention and embodying various constructional features thereof.

Fig. 2 is a right-hand end view of the machine of Fig. 1 with certain parts omitted for purposes of clarifying the explanation.

Fig. 3 is a top-plan view of the front part of machine with certain parts omitted to show the ink agitating and trough actuating mechanisms more clearly.

Fig. 4 is a separate view of the master camshaft showing the various timing and control cams.

Figs. 5, 6, 7 and 8 are sectional views of Fig. 4 taken respectively along the lines 5-5, 66, and 8-8 thereof.

Fig. 5 shows the configuration of the wiper carriage control cam.

Fig. 6 shows the configuration of the web piercing and gripping control cam.

Fig. '7 shows the configuration of the web-feeding control cam.

Fig. 8 shows the configuration of the cam which controls the raising and lowering of the printing quill assembly.

Fig. 9 is a front view of part of Fig. 1 showing the quill assembly and the quill stripper as sembly.

Fig. 10 is a top-plan view of the quill driving mechanism of Fig. 9.

Fig. 11 is a detailed view of the cam-controlled operating mechanism for moving the paint agitating and wiper carriage.

Fig. 12 is a detailed view of the cam-controlled mechanism for moving the trough reservoir into position for loading the printing quills.

Fig. 13 is a detailed view of the cam-controlled operating mechanism for gripping and feeding the printed web.

Fig. 14 is another view of the web gripping and feeding mechanism after completion of one cycle of web feeding.

Fig. 15 is a detailed view of the spring-supported guide for the quill and quill stripper assemblies.

Fig. 16 is a detailed perspective view of the paint agitating and wiping carriage.

Fig. 17 is a sectional view of Fig. 2 taken along the line l'll'| showing the cam-controlled quill stripper mechanism.

Fig. 18 is an end view of Fig. 1'7.

Fig. 19 is a magnified view of a portion of the stripper mechanism to explain its operation.

Fig. 20 is an enlarged diagrammatic view similar to Fig. 19 showing a subsequent step in the stripping operation.

Figs. 21 and 22 are diagrammatic views to explain the paint agitating and wiping mechanism.

Figs. 23, 24, 25, 26 and 27 are diagrammatic views to explain consecutively the quill loading, quill raising, quill stripping, printing, and quill raising steps.

Fig. 28 is a magnified view of a finished indicia printed according to the invention.

Fig. 29 is a plan view of the portion of Figs. 1 and 2 to show the web guiding channel,

Fig. 30 is a sectional view of part of Fig. 3 taken along the line 3030 thereof.

Fig. 31 is a right hand side view of Fig. 30.

Fig. 32 is a sectional view of Fig. 31 along the line 3232 thereof.

Fig. 33'is a sectional view of Fig. 13 taken along the line 3333 thereof.

Fig. 34 is a detail view of the quill wiper mechanism.

Fig. 35 is a bottom view of the modified die and printing assembly.

Fig. 36 is a cross-sectional view of Fig. 35 along the line 3636 thereof.

General method of operation Apart from the novel mechanism which is in-- volved in the machine, it is believed that a clearer understanding of its operation can be had after considering the method of printing which also constitutes an important phase of the invention. For this purpose, reference may be had to Figs. 21 to 27. The paint or other medium which is to form the raised charac'tersis designated by the numeral I, and may be in the form of a paste or liquid suspension of radium-luminous partciles or'crystals-in a suitable liquid vehicle. Preferably, although not necessarily, the medium I is used with a predetermined viscosity. For purposes of simplicity, the medium I will be referred to throughout the subsequent description as paint, although not in any sense by way of limitation thereto. The paint is deposited in any suitable manner in a longitudinally extending channeled member 2 forming a trough within which is adapted to reciprocate the pivotally mounted wiper blade or vane 8. Trough 2 has its surface undercut to receive a quantity of the paint which can be localized therein when the vane 3 moves in the direction of the arrow (Fig. 21 Preferably, this undercut is shaped to conform to the outline of the particular character or indicia to be printed, thus as shown in Fig. 3 it is in the form of a recess 4 in the shape of the indicia 2." Preferably, the vane 3 is of spring metal such as Phosphor bronze and is slightly inclined with respect to the bottom of trough 2 so as to exert a light wiping action on the paint I while lightly and resiliently pressing against the bottom of the trough. Consequently, as the vane moves to the right, it causes the recess 4 to be filled with the paint and the edge of vane 3 strips the excess paint. At each stroke therefore, the level of paint in the recess remains of uniform depth. When the vane 3 reaches the limit of its travel towardsthe right as indicated by the dotted outline (Fig. 21), it is tilted in the opposite direction as indicated by the dotted outline (Fig. 22), and it then moves to the left, back to its original position. By this light wiping motion of the vane, the recess is always kept uniformly filled and aminimum of paint is required at each loading of the quills. Consequently, it is possible to maintain the particles substantially uniformly distributed throughout the paint in the recess 4. Furthermore, the light wiping action of vane 3 subjects the crystals to a continuous gentle agitation without'any substantial pressure which would otherwise reduce the luminous efficiency of the radium-activated crystals. I have found that in order to achieve these effects, it is preferable to make member -.2 or at least its surface and also the lower ends of. the quills of a special alloy which doe: not react deleteriously with the radium paint and which does not result in a caking of the paint on the surface. As an example of. an alloy that has been found successful for these purposes, may be mentioned '18-8 stainless steel. The alloy must have a hard wearing surface preferably of the order of austenitic steel and which is nonmagnetic and polished. As a substitute for the above-noted alloy, Monel and similar hard stainless alloys may be used.

Located above the recess 4 and arranged to be raised and lowered as a unit, is a bank of rotatable printing fingers 5, the lower ends of which are concave as shown in the magnified views of Figs. 19 and 20. For purposes of description, thete fingers will be referred to herein as quills. The quills when lowered into the paint 4 are continuously rotating about their individual axes and each quill picks up a definite quantity of paint. I have found that the concavity of the quill end is necessary du'e to increased surface tension. The quills are then raised out of the paint and each quill carries a certain quantity of paint not only in the concave portion but also on the peripheral portion designated by the numeral 6 (Fig. 19). Before printing, it is necessary to remove this peripheral excess and for this purpose the quills pass upwardly closely through the stripper plate I. This upward movement of the quills is continued until their lower ends are flush with th under surface of the stripper plate whereby the excess paint on'the periphery of each quill is stripped and drops back into the trough 2 (Figs. 22, 23). Instead of moving the quills upwardly to bring their lower end flush with the lower face of stripper plate Lthe latter may be moved downwardly under contr l of a cam o as to control the amount of paint on each quill which projects belowthe under surface of the stripper plate. The paint which is lefton the quills will therefore be roughly elliptical in vertical section as illustrated in the magnified view of Fig. 20. It will be understood of course that because of the-comparatively heavy weight of the paint, it sags below the quill and the volume of paint picked and retained by each quill will depend not only upon the viscosity of the paint but also on the depth and dimensions of the concavity in the quill end. By properly designing the dimensions and shape of this concavity in correlation with the range of viscosity encountered in the paint, the initial and final quantities of paint on each quill can be accurately controlled. As a further control over the amount of paint that is actually transferred from the quills to the final printing surface, a reciprocating wiper blade 8 may wipe across the loaded ends of the quills to remove the paint which projects below the under surface of the stripper plate 1 as indicated in Fig. 20. By making the plate I adjustable with respectto the final'upward position of the quills, the amount of paint which sags below the surface of stripper plate I can be accurately gauged and conseouently the amount that is removed by the wiper blade 8 can likewise be accurately gauged.

When the quills have been properly loaded. they are then lowered, while still rotating, into printing contact with the printing surface or web ,9 (Fig. 26). The quills are then raised above the web 9 to provide, sufficient clearance to allow the loading trough. 2 to enter between the web and the quills whereupon the foregoing cycle of operations is repeated. During this last-mentioned vertical movement of the quills (Fig. 27) a series of pointed fingers II] are forced upwardly through the web 9 adjacent each margin and these fingers are then bodily moved in the direction of the arrow (Fig. 27) to feed web 9 in readiness for the next printing impression. The above cycle of operations is repeated for each successive impression. It will be understood that the quills are arranged in banks, each bank having a crosssectional trace or configuration corresponding to the desired character or impression to be printed. In the actual machine to be described, the trough 2 is movable into and out of the space between the quills and the printing web, the timing being such that it is moved beneath the quills only when the latter are in their completely raised position. Likewise, the wiping and agitatin movement of vane 3 is executed when the trough 2 is in a position where it is entirely clear of the quills. I have found that with the foregoing method employing the constantly rotating concave-end quills, it is possible to print and form directly on the web 9 raised characters of a relatively sharply defined outline wherein the completed character consists of a series of sharply defined discrete raised dots such as shown in Fig. 28. These dots are sufficiently close together so that in the'dark they give the impression of a continuous illuminated indicia. By using dots, the quantity of radium-luminous material that is necessary for the desired luminous area is materially reduced as compared with a correspondingly" thick indicia of uniform thickness. The sharpness and luminous efficiency of the individual dots constitutin the printed indicia probably is caused by the fact that the only physical engagement between the quills and the printing surface is that which may occur at the comparatlvely sharp thin edge I I (Fig. 19) of each quill. Furthermore, in order to deposit the paint on the printing surface or web, it is not necessary to subject the web or the paint to any appreciable pressure from the quills. While I am not entirely sure as to what causes the paint to be withdrawn from the quill ends on to the printing surface, it is likely that it is due to the fact that the quills are rotating and because of the special alloy of the quill ends there is a greater adhesive force existing between the web and the paint as compared with that normally holding the paint in the quill concavity. Preferably, the quill ends should be made of a special alloy similar to that of the trough 2 so as to exert a minimum adhesive force on the paint and so that once contact is made between the paint in the quill end and the web 9, the surface tension of the paint in the quill concavity is broken and gravity assists in depositing the paint on the web. If desired, the downward movement of the quills can be regulated so that the edges II of each quill execute a slight bite into the web.

Detailed description of the machine A machine for carrying out themethod above described is shown in detail in Figs. 1 to 20. Referring more particularly to Figs. 1, 2 and 3, the machine comprises a bed plate I to which are rigidly fastened five main supporting pillars IOI-I The pillars IOI-I04 support at their upper ends a platform I06 on which is supported the paint trough 2, and the mixing and inking carriage designated by the general numeral I01 and shown in perspective in Fig. 16. The pillar I06 telescopically supports the sleeve I08 which in turn carries the printing quill and stripper assembly designated generally by the numeral Mounted at the right-hand rear portion of plate I00 is a suitable power motor H0 which drives, by a belt III, a pulley II2 fastened to shaft II3. Shaft H3 is provided with suitable bearings in the brackets H4, H5, carried respectively by bed plate I00 and platform I06,'and has fastened to its left-hand end a worm II6. Worm II6 meshes with worm-wheel II1 aflixed to cam-shaft IIB supported in suitable bearing brackets II9, I (Fig. 4). Aflixed to shaft 8 are flve cams four of which are shown in detail in Figs. 5, 6, 7, 8 respectively. The angular position of the cams on the shaft II8 are as shown in Figs. 5 to 8 so as to provide the required timing between the various operations to be described. Cam I2I controls the movement of the ink agitating and wiping carriage. Cam I22 controls the web piercing fingers I0, while cam I23 controls the feeding movement of the printed web. Cam I24 controls the raising and lowering of the printing quill and stripper assembly I09. Shaft II8 also has fastened to its forward end a bevel gear I25 meshing with another bevel gear I26 which is attached to a stub shaft I21 supported in bearing brackets I28, I29, fastened to plate I00. Shaft I21 carries a cam I30 for controlling the movement of the paint trough into and out of loading engagement with the quills.

Fastened at the opposite ends of platform I06 are guide rails I3I, I32 (Figs. 1 and 3), which extend parallel to each other and to the rear edge of platform I06 where they have vertical stops I33 to limit the backward movement of the paint trough 2. Trough 2 consists of a. metal casting having a flat bottom and two side walls I34, I35, having flat upper faces to serve as guide rails for the carriage I01 (Fig. 16). In accordance with a feature of the invention, the bottom wall of the trough is of any well-known stainless steel alloy but preferably a non-magnetic alloy of the type known to the trade as 18-8 stainless steel. This 15 alloy -1 have found enables the radium paint to be wiped back and forth with a minimum of caking and without danger of contamination or corrosion on the trough surface. However, if desired, the trough may be of ordinary steel and a layer I36 of the above alloy may be fastened in any suitable manner to the bottom and to the interior surfaces of the side walls of the trough. The trough carries at opposite ends downward extending flanges I31, I38, in which are rotatably mounted rollers I39, I40, I and I42, which ride upon the guide rails I3I, I32. Each of the rollers has a shoulder bearing against the side walls of the rail to guide the trough thereon.

The trough tends to assume a position forwardly of the platform I06 limited by a pair of stops I44, I45 attached to the rails, this forward position being controlled by tension springs I46, I41, each having an end fastened to the trough and an opposite end fastened to corresponding brackets I48, I49, attached to platform I06. Preferably, the forward ends of brackets I46, I49, are disposed below the level of platform I06 thus tending to maintain the trough in contact with the guide rails.

Mounted for rolling movement on the side walls I34, I35, is the paint wiping and agitating carriage shown in detail in Fig. 16. This carriage comprises a pair of vertical side walls I60, I5I, which are rigidly held by the cross braces I52-I55. Rotatably mounted at the ends of braces I52, I53 are rollers I56, I51, which ride upon the corresponding members I34, I35. A similar set of rollers I58, I59 engage the under surface of the trough. Rotatably supported in the side wallsis a shaft I60 which has fastened thereto by screws I6I the wiper blade or vane 3 of suflicient size with respect to the carriage so that it lightly wipes the bottom and side walls of the trough 2 as the carriage rides to the left and to the right (Fig. 1). Preferably, vane 3 is of Phosphor bronze or similar springy material which does not react or corrode when in contact with the paint. Vane 3 is arranged to assume two angular positions with respect to the trough. Thus-when the carriage I01 is moved to the right (Figs. 1 and 3), the vane is inclined to form an angle opening to the right (Fig. 21). When it reaches the extreme left-hand position, it is automatically rotated so that during the reverse movement of the carriage, it is inclined in the opposite direction (Fig. 22). For this purpose, shaft I60 has attached thereto an arm I62, the upper end of which is V-shaped (see Fig. 1) Bearing against the inclined ends of arm I62 is a roller I63 rotatably mounted in a slot I64 in an arm I65 pivotally attached at I66 to an extension I61 of side wall I50. A coil spring I66 has one end attached to the wall I50 and the other to arm I65 thus maintaining roller I63 in engagement with an inclined edge of arm I62. The members I62, I63, form a modified form of toggle which can be broken in one position or the other by engagement between the roller I69 and the stops I10, I1I, fastened to platform I06. Thus, assuming the vane is in the position shown in Fig. 16, and the carriage I01 is near its extreme right-hand position (Figs. 1 and 3) where the roller I69 engages stop I10, slight further movement of the carriage to the right rotates the arm I62 and shaft I60 in a clockwise direction (Fig. 16). The inclined end of arm I62 therefore rotates roller I63 and vane 3 m a counterclockwise direction in readiness to execute its reverse wiping stroke (Fig. 22). Carriage I01 also carries adjacent the ends on one side a pair of rollers I12, I13, rotatable substantially at right angles to rollers I56. Preferably the rollers I 12, I13, are mounted so that pable of limited tilting movement with respect to a vertical axis.

The movement and alignment of carriage I01 is controlled by a trolley member I80 comprising two parallel'plates I8I, I82, rigidly held in spaced relation by three cross braces I83, I84, I 85, which also serve as shafts for the respective guide rollers I96, I81, I88. The trolley rides on a rail I89 fastened to pedestals I90, I9I, attached to platform I06. Attached to the lower side of the trolley at opposite ends are L-shaped brackets I 92, I93, spaced apart a greater distance than the overall distance between the rollers I12, I13. The purpose of this is to insure that the carriage I01 is properly engaged by the trolley brackets I92, I93, should the carriage be slightly out of alignment with the trolley when the trough moves to its forward position. Because of the slight tilting movement of the rollers I12, I13, the carriage automatically aligns itself with the trolley. The trolley I is to assume its extreme left-hand position (Fig. 1) under control of spring I94 having one end attached to bracket I95 fastened to pedestal I90 and the other end attached to projection I96 on the trolley. The projection I96 is also connected to a belt or rope I91 passing around a small pulley I98, the opposite end of the belt being attached at I99 to a friction drum 200, joumalled in the bearing plates 202, 203, which are held in rigid spaced relation by cross braces 204, 205, 206. Shaft 20I carries a toothed gear 201 which meshes with and is driven by a larger toothed gear 208 rotatable on its shaft 209 supported in plate 202. The gear-208 is driven under control of cam I2I (Figs. 1, 4 and 5). Fortthis purpose,

there ispivotally attached at 2I0 (Figs. 1 and 11) to plate I00, an arm 2 which carries a cam follower roller 2 I2 which is engaged by cam I2 I.

The upper end of arm 2 is pivotally connected to link 2I3 whichis pivotally attached at 2 to gear 208. By this means the relatively small throw of cam I2I causes a greatly magnified rectilinear movement of thetrolley I80 and thus of the carriage I01.

When the carriage has been moved to its extreme right-hand position, and then has been restored to its extreme left-hand position so as to subject the paint to a cycle ofwiping and agitation in the trough 2, the trough together with the carriage is moved towards the rear recess 4 is in vertical of the. machine where the alignment with the transfer and printing quills 5. For this purpose, there are attached to platform I06 (Figs. 2 and 3), a pair of plates 2I-5, 2I6, which carry two sets of roller guides 2I1, 2I8, 2 I 9, 220, between which passes the horizontal arm 22I. Arm 22I has at its rear end a block 222 which is arranged to engage the trough 2 to push it backward against the tension of the springs I46, I41. For this purpose, there is attached to plate I00 a bracket 223 in which is pivotally mounted an am 224 carrying a cam follower roller 225 to engage cam I30. Follower 225 is maintained in engagement with cam III by tension spring 226 connected between arm 224 and bracket 221 fastened to plate I00. Arm 224 has fastened to its upper end an L-shaped member 228 which engages roller 229 mounted in bracket 230 on member 22I. A tension spring 230a contains the arm 228 in engagement with roller 229. When follower 225 is on the low part of cam I22 (Fig. 12), member 22I is in its forward position consequently thetrough 2 is likewise in itsforward position (Fig. 3) under control-of springs I46, I41. After the carriage I01 has completed its forward and backward cycle of movementin the trough 2 to mix and agitate the paint in recess 4, cam I22 causes member 22I to move rearwardly thus forcing the trough to move rearwardly. While the trough is thus moving, the quill assembly unit I99 is gradually raised under control of cam I24 (Fig. 9) so as to provide sufficient clearance to allow the trough to move under the quills.

The quill printing m As shown more clearly in Figs. 1, 2, 9 and 10, the printing unit comprises a heavy hollow metal sleeve I08, which has fastened thereto a forwardly extending'bracket 232 (Fig. 2). Fastened to bracket 232 is a platform- 233 to the front edge of which is attached a similar but thicker platform 234. Fastened adjacent opposite ends of the platform- 234 are two channel guides 285, 236 in which are adjustably movable blocks 221, 238, carrying at their forward ends rollers 22!, 240. These rollers are arranged to ride upon corresponding vertical fiat guides 2, 242, in the form of angle irons rigidly fastened at their lower ends to plate I00. Blocks 231 and 238 each have a threaded shank 243 threaded hto a plate 244 carried by guides 235. 236, whereby the rollers can be adjusted horizontally against the guides 24I, 242. Rigidly fastened to platform 234 in'spaced relation therebelow is'another similar plate 245, these plates being fastened together in spaced relation by screws 246 and-sleeves 241 (Fig. 17). Likewise, fastened beneath plate 245 is the stripper plate 1 which is supported on guide members 249, 250, threaded into plate 245. Guides 249, 250, have compression springs 25I', '252, located between the heads 253 of the guides and the other surface of plate 1. Normally therefore, plate 1 tends to approach plate 245 but are held in spaced relation by cams 254, 255 pivotally at.- tached to the ends of plate 245 and adapted to engage rollers 256, 251, carried by the ends of plate 1. Each cam has an operating arm 268 whereby the plate 1 can at the appropriate instant just the right amount so that its under surface is substantially flush at the extreme lower ends ofthe quills as illustrated in the magnified view of Fig. 20. If desired, the cams 254, 255, are adjustably fastened on the shafts 259 by set screws 260 whereby the amount of retraction of the quills 5 with respect to the plate 1 can be accurately regulated.

Rigidly fastened to platform 234 are two pedestals 26I, 262, across which is fastened by bolts 263, a plate 264. Likewise, supported in tions in plates 1, 245,

be moved downwardly alignment. While there are the same number of perforations in all the plates, the perforations in plates 1, 245 and 234 are closer together than the perforations in plates 264, 266 although as a whole the perforations in the lower plates are. directly beneath the perforations in the upper plates 264, 266. Rotatably mounted in the perforations in plates 264, 266, are a series of spindles 261, each of which has fastened to its upper end an individual toothed gear. 268, all the gears being mutually in mesh as shown more clearly in Fig. so that adjacent spindles rotate in opposite directions. These small gears are driven at a predetermined rate by means of a gear train 269, 218. Gear 218 is affixed to shaft 21I journalled in suitable bearings 212, 213, carried respectively by plates 266 and 264. Shaft 21I has afllxed to its lower end a wormwheel 214 driven by a worm 215 on shaft 216 journalled in bearing bracket 211. The rear end of shaft 216 (Fig. 2) carries a bevel gear 218 meshing with a similar bevel gear 219 whose shaft is journalled in bearing bracket 288. An extensible flexible shaft 28l' connects gear 219 with gear 282 afllxed to. the shaft of motor II8.

Likewise, mounted for rotation in the corresponding openings in plates 1, 234 and 245 are the series of quills 5 shown in an enlarged cross section in Figs. 19 and 20. Each quill is connected to the corresponding spindle 261 by a flexible shaft 283 such as a fine steel wire or the like so that the quills rotate in unison with the spindles 261. v

The weight of the quill assembly I89 is such that normally it is supported by cam I24 which engages roller 284 carried by the roller end of support sleeve I89. When the roller 284 is riding on the lowest part of cam I 24, quills 5 are in printing contact with the web 9. After printing, cam I24 rests the quills to their maximum height thus allowing the trough 2 to pass underneath the quills as above described. While the trough is held stationary under the quills, the latter start to descend until roller 284 engages the low point 285 of the cam and the quills are lowered just sufllciently to allow their concave ends to be immersed in the paint in recess 4. Cam I24 then rests the quill sufllciently to clear the sides I34, I35 of the trough and thereupon cam I22 allows spring 226 to retract arm 229 whereupon springs I 46, I41, restore the trough to its forwarding position where itis clear of the quills.

Just before the quills are lowered to their printing position, the web 8 is fed the desired amount to present the next area to be printed. For this purpose, the web is carried on a pay-off reel 286 supported for rotation on two spaced arms 281, 288, fastened to platform I86. Arms 281, 288, also carry a pair of guide rollers 289, 298 (Fig. 2), between which the web 9 passes. As shown in Fig. 29, the top of platform I86 in line with the reel 286 has fastened thereto a pair of guide rails 29I, 292, between which the web passes. A plurality of spring fingers 293 are attached to the rails to hold the web flat against the platform. The left-hand end of platform I86 is provided with two slots 294,295 adjacent the sides of the web guiding channel, and fastened to the platform in spaced relation thereto are a pair of slotted plates 296, 291,- each having a 3 slot of the same size and in alignment with the slots 294, 295. The web 9 is arranged to be teeth I8 which are arranged to be moved vertically to pierce the web, and thereafter they are moved bodily a predetermined distance to the left (Fig. 13) to feed the web the required distance. 'I'hereupon member 298 is ioweredto disengage the teeth I8 from the web and the feed device is returned to its initial position ready for the next feeding step. The piercing movement is controlled by cam I22 and the feeding movement is controlled by cam I23. Cam I22 engages roller 388, carried by arm 28I pivotally attached at 382 to plate I88. Arm 38I is pivotally connected through link 383 which in turn is pivotally attached to a lever arm 384 fastened to a shaft 385 mounted in bearing brackets 383, 381 (Figs. 13 and 29). Shaft 385 also has fastened thereto a lever arm 388 which has pivotally attached thereto an arm 389 pivotally connected to a bracket 3I8 carried by platform 3I I. Platform 3 is pivotally attached at 3I2 to a bracket 3I3 supported beneath platform I83. Consequently, as the .high part of cam I22 engages roller 388, the left-hand end of platform 3 is raised around the pivot 3I2 and forces r the left-hand end of member 298 with its teeth I8 in a substantial vertical direction a sufllcient distance to cause the teeth I8 to pierce the web 9. Thereupon, the high part of cam I23 engages a roller 3 carried by the arm 3I5 pivotally attached at 3I6 to plate I88. Arm 3I5 is likewise pivotally attached at 3" to the member 298 whose roller 3I8 rests on the platform 3i I. Consequently, when the high part of cam I23 engages the roller 3, the member 298 is moved to the left against the force of tension spring 3I9, thus feeding the web 9 the predetermined distance.

For the purpose of removing the excess paint which projects below the stripper plate 1 as above described, there is provided a horizontally movable wiper blade 8 (Figs. 17, 18 and 34), which is supported by two arms 325, each attached to corresponding rollers 326, mounting for rolling movement in corresponding longitudinal grooves 321 in the front and rear vertical sides of plate 1. A spring 328 normally holds the rollers and blade 8 adjacent one end of plate 1. Arms 326 are connected by cord 329 passing over a pulley 338 and thence to the upper end of lever 33I pivoted at 332. The normal position of lever 33I is indicated in dotted outline in'Fig. 34 where it engages stop member 333.

Attached to cam shaft II8 (Figs. 4 and 34) is anarm 334 which at the right instant when the 7 Referring to Fig. 35 there is shown in magnified form a portion of the printed web 9 wherein the indicia has been printed as described. As will be seen the indicia is formed in a series of discrete raised dots 336 each of spherical sector shape corresponding to the shape of the depressions in the quill ends. Because of the fact that the quills arerotating while the paint is being deposited on web 9, each dot has a sharp outline and if desired a greater or less spacing may be provided between succeeding dots. Notwithstanding that the dots are'spaced, when the indicia is viewed in the dark, itappears to be a continuous strip of light. This enables a considerable saving in the quantity of radium luminous material necessary to form the luminous indicia. It will be understood of course that in printing such devices as clock dials and the like with a plurality of separate indicia, that the quills will be arranged in groups, each group corresponding to its respective indicia to be printed and merely for simplicity of the drawings, the machine is shown as printing a single indicia. In order to reduce the load on the driving motor during the raising of the quill-stripper assembly or cam I24, the assembly is partially supported by two bowed leaf springs 331, 338 (Fig. 15) which have their lower ends fastened to the plate I and their upper ends fastened to a bracket 339 (Fig. 2) carried by the sleeve 231. The springs 331 and 338 tend to push the quill-stripper assembly upwardly but the weights of the latter is sufllcient to maintain roller 284 in engagement with the cam I24 so that when the cam rotates to raisethe assembly, it is assisted by the springs 331 and 338. Preferably the rear pedestal I08 is joined to the pedestals 190,15", by rigid inclined brace members 340, I. r

If it. is desired to print the raised characters each in a continuous strip or rib as distinguished from a series of dots, an arrangement such as shown in Figs. 35 and 36 can be employed. In this embodiment, the quills 5 pass through a perforated die member 345, the lower end 346 of which is chamfered to a sharp edge 341 and forms a continuous groove or channel bounding the quills 5. The die is slidable in the stripper plate 1 and is supported from the upper plate 245. For this purpose, die 345 carries a plurality of radially extending pins 348 which register with inclined slots 349 in a ring 350. Ring 350 has an outwardly extending horizontal flange which rides on a corresponding inwardly extending horizontal flange on ring 35I fastened by screws 352 to plate 245. Fastened to ring 350 is an operating arm 355 which is adapted to be engaged by member 354 which is operated either from the main cam shaft H8 or if desired a fixed abutment may be provided on the platform I06 so that during the downward movement of the quill-stripper assembly as above described, and just before the quills are about to assume their printing position; the said abutment engages the arm 353 torotate to ring 350 whereby the die 345 is moved downwardly so that the edge 341 engages the printing web. Since the die 345 is carried by the member 245, it normally projects below the surface of the stripper plate 1. However, during the downward movement of the quill-stripper unit, the engagement of the arm 353 with member 354 raises the die 345 so that the lower ends of the quills project below the under face of member 1 and these ends can dip into thepaint trough for loading asabove described. After the quills have been loaded, the member 1 is moved downwardly to the dotdash line position as already described so that its under face is in substantially the sameplane with theends of the quills. Consequently, the wiper blade 8 can then move across the quill ends to strip off the excess paint as above described and during this downward movement the member 355 also strips the excess paint off theperipheral end of the quills as hereinabove described. After the quills have been stripped the unit is lowered to printing position as already described so that the edge 341 engages the printing web and the paint is discharged from the lower ends of the quills on o the printing surface. During this discharge, the quills are constantly rotating as already described and the paint which is discharged is confined to the outline of the character as determined by the shape of the groove or channel in the lower end 346 of the die. By this arrangement therefore, the paint is deposited in a continuous raised rib, the boundaries of which are sharply delineated by the edge 341.

What I claim is:

1. The method of printing which comprises immersing a plurality of hollow-ended quills in the printing medium, rotating the quills around their individual longitudinal axes while immersed, and transferring the printing medium from the quills to a receiving surface while maintaining the quills rotating.

2. The method according to claim 1 in which adjacent quills are rotated in opposite direc tions.

3. The method of printing which comprises immersing the hollow ends of a plurality of printing quills in a printing medium, rotating the quills around their individual longitudinal axes to cause the hollow ends to pick up a quantity of the medium, bringing the loaded quills into printing relation with a receiving surface, and rotating the quills to deposit the printing medium thereon.

4. The method of printing employing a plurality of hollow-ended printing quills arranged in banks having a conformation corresponding to indicia to be printed, which comprises rotating the quills around their individual longitudinal axes while immersing their hollow ends in a viscous printing medium, withdrawing the quills, stripping excess medium from the quill ends, moving the quills into printing relation with a receiving surface, and rotating the quills while in such printing relation.

5. The method of printing employing a printing medium of a liquid suspension of heavy particles such as radium-luminous particles which tend to separate out, which method comprises applying the medium to the ends of a bank of printing quills while maintaining the quills in rotation about their individual longitudinal axes, transferring said medium from said quills to a receiving surface, and maintaining the medium in constant agitation from the initial loading of the quills to the final printing on said surface.

6. The method according to claim 5, in which the medium is loaded on to the quills andis transferred therefrom to the printing surface with a minimum of pressure on the said particles.

7. The method of transferring radium-luminous paint and the like from a supply receptacle to a printing surface employing a bank of concave-ended quillswhich comprises, loading the quills by immersing and rotating them around their individual longitudinal axes in the pain,

ceiving surface to form the indicia with a series of discrete raised dots of said paint.

9. The method according to claim 8 in which the ends of the quills are located all in the same plane, and the loaded ends thereof are stripped of excess paint prior to transfer to said receiving surface.

10. A surface printing device comprising a bank of printing fingers each having a solid concave end to receive a quantity of printing medium, said fingers being arrayed so that their cross-sectional trace conforms to the shape of the indicia to be printed, and means to maintainsaid fingers in rotation about their individual longitudinal axes during printing.

11. A printing device according to claim 10 in which said fingers are mounted so as to be moved as a unit into and out of printing relation with a receiving surface.

12. A surface printing device comprising a bank of solid but concave-ended quills each arranged to receive a quantity of printing medium only in the cavity at the end thereof, and means to maintain each quill in rotation about its axis while it is being loaded with printing medium and while it is in printing relation with a receiving surface.

13. A surface printing device according to claim 10 in which the ends of said fingers are of metal having a minimum of adhesive force with respect to the printing medium, the dimensions of the concave end being correlated with the viscosity of the printing medium so that the latter is retained therein mainly by surface tension.

14. A printing device according to claim 10 in which the ends of said fingers are of stainless steel alloy.

15. A printing device according to claim 10 in which the ends of said fingers are of an alloy of the non-magnetic stainless steel type.

16. A surface printing device according to claim 10 in which all said fingers are individually rotatable about their respective longitudinal axes and are connected to a common driving shaft whereby they are maintained i rotation around their individual longitudinal axes during loading and printing.

17. In a surface printing device of the character described, a frame, a plurality of concaveended printing fingers carried by said frame, means to maintain each finger individually rotating about its longitudinal axis, and means to move said frame whereby said fingers can be brought into and out of printing relation with a receiving surface while they are rotating.

18. A surface printing device according to claim 1'7 in which said frame carries upper and lower horizontal perforated plates, and a pinrality of driving spindles are mounted for rotation in the upper plate, each spindle being connected by an individual flexible shaft to a corresponding one of said fingers.

19. A surface printing device comprising a bank of vertically mounted rotatable spindles arrayed to conform in cross-sectional trace to the shape of indicia to be printed but with the trace larger than the indicia, a bank of vertically mounted hollow-ended printing quills arrayed to conform in cross-sectional trace to the shape of the indicia but with a trace smaller than the first-mentioned trace, and an individual flexible shaft connecting each spindle to a corresponding quill.

20. A printing device according to claim 19 in to conform in cross-sectional trace to the shape which each spindle carries a toothed gear and with adjacent gears in mesh, all said gears being driven from a common drive whereby adjacent quills are rotated in opposite directions.

21. In a machine of the character described, a vertically movable printing quill unit having a plurality of solid but concave-ended printing quills, a longitudinally movable paint trough unit, a reciprocating wiper blade unit for said trough. a wiper unit for said quills for stripping excess paint from the ends of said quills prior to printing, a single source of motive power for said units, and timing means for controlling the movement of said units in the following sequence; reciprocating said wiper blade to agitate the paint in vertically movable frame, a. plurality of hollowended printing quills carried by'said frame each rotatable for loading and discharging printing medium, a stripper plate carried by said frame and vertically movable with respect to the quill ends,'means to move the plate so that its lower face is substantially flush with the lower ends of said quills, a wiper blade with its wipingedge in contact with the under face of said plate, and means to reciprocate said blade after said quills have been loaded and while the lower surface of said plate is substantially flush with the quill ends.

23. In a surface printing machine of the character described, a plurality of rotatable printing quills arrayed to conform in cross-sectional trace to the shape of the indicia to be printed, means to maintain said quills in continuous rotation during printing, a member bounding the lower ends of said quills comprising means through which the quills pass, the lower end of said memher having a channel of the shape of the indicia, cooperating with the quills to define the boundaries of the printed indiciar 24. In a machineof the character described, a plurality of rotatable printing quills, a perforated plate through which the lower ends of the quills project for printing", said quills being arrayed to conform in cross-sectional trace to the shape of the indicia to be printed, a member bounding the said quills and slidably mounted in said plate with respect to said quills, means to move said plate so that in oneposition its under face is substantially flush with the ends of the quills and in another position the quill ends project beneath said under face, and means effective when said quills are about to assume a printing position to move said bounding member into contact with the printing surface.

25. A machine according to claim 24 in which said bounding member is in the formof a perforated die slidably mounted in said plate, said die when the quillsare in printing position being moved so that its lower bounding edge i substantially flush with the lower ends of the printing quills. I

26. A printing die comprising a perforated solid member having a series of perforations arrayed of the character to be printed, the lower face of said die being formed, with a bounding channel, and a plurality of printing quills passing through 

